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%I #12 Nov 04 2020 16:56:27
%S 4,6,9,10,15,21,22,25,34,38,39,46,49,51,55,57,58,65,69,87,91,93,94,
%T 106,111,115,119,121,123,133,141,142,146,159,169,177,183,202,205,213,
%U 214,218,219,226,235,237,249,253,254,259,262,265,267,274,289,291,295
%N Semiprimes that are the sum of two triangular numbers.
%C Semiprime analog of A117048 Prime numbers that are expressible as the sum of two triangular numbers.
%F A020756 intersection A001358.
%t With[{nn=60},Take[Union[Select[Total/@Tuples[Accumulate[Range[0,nn]],2],PrimeOmega[ #] ==2&]],nn]] (* _Harvey P. Dale_, Nov 04 2020 *)
%Y Cf. A001358, A020756, A117048.
%K easy,nonn
%O 1,1
%A _Jonathan Vos Post_, Aug 02 2006
%E Missing a(2) and a(19)-a(53) from _Giovanni Resta_, Jun 13 2016
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